Germacranes and m-menthane from Illicium lanceolatum.

Three new germacrane sesquiterpenes and a new m-menthane monoterpene were isolated together with four known compounds from the pericarp of Illicium lanceolatum, an adulterant to star anise (Illicium verum). All compounds were isolated from Illicium plants for the first time. The absolute stereochemistry of all germacranes and m-menthane was established by a combination of NMR and the modified Mosher's ester method. The biological activity was evaluated on SH-SY5Y neuroblastoma cell line. (1S,5R,7R)-1,5-Dihydroxygermacra-4(15),10(14),11(12)-triene (at 62.5 µM) and (1R,5R,7R)-1,5-dihydroxygermacra-4(15),10(14),11(12)-triene (at 15.6 µM) promoted the proliferation of SH-SY5Y by 36.2% and 45.8%, respectively, after 48 h incubation, indicating potential neurotrophic activity.